Deep Brain Stimulation (DBS) is becoming an acceptable therapeutic modality in neurosurgical treatment of patients suffering from various conditions, including, for example, chronic pain, Parkinson's disease, essential tremor, dystonia and other medical conditions. Other electro-stimulation therapies have also been carried out or proposed using internal stimulation of the sympathetic nerve chain and/or spinal cord, etc.
One example of a prior art DBS system is the Activa® system from Medtronic, Inc. The Activa(® system includes an implantable pulse generator stimulator that is positioned in the chest cavity of the patient and a lead with axially spaced apart electrodes that is implanted with the electrodes disposed in neural tissue. The lead is tunneled subsurface from the brain to the chest cavity connecting the electrodes with the pulse generator. These leads can have multiple exposed electrodes at the distal end that are connected to conductors which run along the length of the lead and connect to the pulse generator placed in the chest cavity.
Generally described, electrostimulation is carried out by delivering a pulse of desired frequency and amplitude in the target cranial tissue, typically using an implanted lead system. These lead systems have electrodes that are exposed at a distal end to contact the target cranial/neuronal tissue. The lead systems are connected to an implanted pulse generator at the other opposing end (proximal end). The distal end of the lead system is implanted in the desired cranial anatomy by stereotactic surgical procedures. In this procedure, a microelectrode system is advanced in the cranial tissue, typically based on MRI, CT or PET images acquired prior to the procedure. The target location for lead implantation in the cranial anatomy may be determined by measuring the electrical signal (EPG) signature of the specific anatomy using a microelectrode system. Typically these procedures are long and there is a clinical need for real time imaging guidance.
Notwithstanding the above, there remains a need for alternative MRI compatible medical lead configurations.